For historical/backward compatibility reasons, MAUI.Controls only supports 2-state visibilty (via the IsVisible property). A view is either visible or it is collapsed (meaning it takes up no space).
Some other UI platforms (e.g., WPF and Android) also support a "hidden" visibility state, where the view is not visible but it still takes up space. The underlying MAUI.Core library actually supports all three states on all of the platforms (which is why the Core Visibility enum has three values).
Users who want to handle visibility differently in a MAUI.Controls app can do so with some custom code.
Mapping IsVisible = false to Visibility.Hidden
The basic-remap branch shows how to do this by modifying the Visibility mapping - IsVisible = true continues to map to Visibility.Visible, but IsVisible = false maps to Hidden rather than Collapsed.
The decorator-remap branch shows an alternate way to handle this by creating decorator for IView which modifies how IsVisible is interpreted when updating the Visiblity property in Core.
The attached-property branch demonstrates the creation of an alternate attached property on View which can handle 3-state visibility. The actual work of mapping the states to the native properties on each platform is handled in a new mapping added at startup.